Researchers at the University of Ottowa have developed a concept that would reduce the size of lenses by a huge margin and effectively eliminate the size of modern optics if combined with metal. The team did not deal with the elements of the lens, but with the space between them.
Researchers explain that the last few centuries of optical work have relied on refinement and combination of lenses for better control of optical characteristics. Based on this, the relatively new nanotechnology has allowed the development of metals that have the ability to shrink optics to a large extent.
But unaddressed in the development of metals is the requirement for space between the optical elements. No matter how small the lens is, it still relies on space to create images. This space will always be an obstacle to miniaturization, unless it is addressed directly.
As described in the summary of the research work, the researchers emphasize the issue of space, presenting the concept and experimentally demonstrating an optical “space plate”
“… optics that effectively propagate light at a distance that can be significantly greater than the thickness of the plate. Such optics would shrink future imaging systems, opening up the possibility of ultra-thin monolithic cameras. More broadly, a space plate can be used to miniaturize important devices that implicitly manipulate the spatial profile of light, such as solar concentrators, collimators for light sources, integrated optical components, and spectrometers. “
The team, led by Dr. Orad Rechef, a senior doctoral student in the Robert Boyd group, and Dr. Jeff Lundin, a Canadian research department in quantum photonics and an associate professor in physics at the University of Ottawa, spoke with Phys and explained that the team wanted to look at the way light is propagated between optical elements and to deal with aspects of this process for which lens elements can do nothing.
In an interview, Dr. Resheff said that light naturally propagates when it travels, and any optical device currently in use relies on that propagation to work. As an example, he points to the big difference between an eyepiece and a lens in a telescope or a camera lens: both rely on this distance and propagate to function properly.
But this gap and other flaws in the design of the lens take up a lot of space and his team developed what they call a “space plate”, which is able to take the same light propagation and compress it into an “analogue” of the lens and allow entire image systems to become drastically smaller as a result.
“We considered what would happen if you manipulated the light based on the angle rather than the position of the light beam,” Dr. Lundin told Phys. “The lens acts through the position of the beam. Angle is a whole new field and no one has shown that it can be turned into something particularly useful. We have identified a useful application that compresses space. And then we showed that we can actually design and experimentally demonstrate plates that do just that. “
Dr. Resheff says this development would theoretically allow lens manufacturers to shrink any large devices that were previously considered impossible to miniaturize.
“To design it, we need to come up with a new set of rules that are incompatible with those used in lens design. “Nobody knows what they are, it’s like the Wild West,” he said. “Surprisingly, optical elements such as lenses have existed for millennia and the rules for their design have been well understood for more than 400 years, and yet we are still discovering such basic new optical elements for images.”
The space plate can work in tandem with metal to significantly reduce the size of the optics to the point where, for example, graphics, the lens appears aligned with the camera’s sensor.
Researchers say they are currently working to develop the next generation of technology to increase the compression factor and improve overall performance.
“We already have some projects to increase the compression ratio from five to over 100 times and to increase the overall transmission. To keep doing this, we need to come up with a whole new design paradigm, ”says Dr. Lundin.
While metallics threaten to completely eliminate the impact of the camera in modern smartphones, the space plate in combination with metalens technology has the potential to eliminate modern lenses completely. This is a possible revolutionary development in the field of optical science and the full research report can be read here.